@JonFleming I use Opera on a Windows Desktop, Pixel Phone and Tablet.
As a workaround from Opera on my Desktop, I Open Bookmarks, Other Speed Dials.
I see a List of other Devices "Pixel Phone" and "Pixel Tablet".
I can then Copy and Paste Speed Dials between the Device folders.
I also have another folder named Master which contains all my Speed Dials as a Backup.
J